Okay, I'll give a stab at it. Since Luddite played the last turn, these screenshots are from the beginning of the turn (except that I've copied moving our sentry chariot onto the hill overlooking Nuremburg).
Our plan is to take out Sian's metals and the army he's throwing against Fierce at the opportune moment. If we can take out his metals early on, then we should be able to take his island cities easily, as there will be no crossbows or pikes to go against our maces and HAs.
We looked at a lot of different ideas, and most of them were centered around these part of the map:
We looked a long time at how we could amphibiously assault iDOLM@STER without Sian seeing the galleys approach. Since Sian has sight into Pumping Iron that means the galley would have to approach from the tile 1E of PI. So the only way to threaten his city in 1 turn would be by building a fort over one of our mines. While it'd be a fun idea to try, it isn't very feasible. We have one worker in the area, and it would have taken him 7 turns to build the fort. So no boating, but we did find a way to scout the town without him knowing.
I circled two of our 5xp horse-units in the upper part of the map. I'm not sure which one Luddite moved, but one of them was moved onto the galley this turn. We can promote it to sentry and scout iDOLM@STER each turn without Sian knowing we are up to it, by doing the following pattern:
1. Galley enters Pumping Iron and unloads the sentry.
2. Sentry moves 2 tiles S to the plains hill. This gives it sight onto iDOL and we snap a screenshot.
3. Galley moves 1E of Pumping Iron.
4. Sentry moves N, NE back into the galley.
This way the sentry and the galley are never in sight of Sian (remember that he does have sight into the city of Pumping Iron).
We suspect that the town is lightly defended, if at all. (Last time we looked, it only had 2 catapults and a warrior in it.) So the turn we decide to attack, a group of Impi (3 or 4) will move to the pink square, 1N of the iron. From this square they can threaten to attack iDOL as well as pillage the iron. Undoubtably he whips a unit in iDOL and pillage the mine and the road, sacrificing a few Impi.
At the same time, we are watching this:
Sian bombed away most the defenses of Nuremburg, and we assume he countinues to attack. I'm not sure he can take the town, but basically on the turn we deem appropriate, we attack Sian's stack. Our troops will stay put in Aachen (except the Impi, they are heading to Prague to raid the iron), where they are 4 tiles away from Sian's stack. The turn that Nuremburg falls, Fierce's culture will disappear and we will have free shots at that stack. We also have the option of going straight for Sailor Moon and bypassing the stack.
So every turn we are going to be scouting iDOL, and we'll be keeping eyes on the battlefield. Another thing we are watching is news of Yuris' advance. If the capital gets taken then we need to speed up our attack in a big way. The tricky part will be finding the right moment to attack. The soonest we can go is on t104.
In the meantime, LongGoodbye and 1 other town (I can't remember which) are building maces & xbows. These will be invading Sian's island when the time comes. We want to show the galleys after we've cut the iron; hopefully this keeps him from whipping pikes & xbows on the island.